'His enthusiasm rubbed off on many of his visitors, who carried the latest news of Vesuvian experiments with them across the Continent and to America. His investigations culminated in a book describing the ‘fields of fire’ or Campi Phlegraei, as he titled his ‘observations of the volcanos of the two Sicilies’. He spent more than £1300 producing the edition, adding a supplement to cover the eruption of 1779. It was one of the most lavish and expensive publications of the 18th century, marking both a high point and a dead end in Enlightenment vulcanology.'
https://www.lrb.co.uk/the-paper/v45/n19/rosemary-hill/smoke-and-lava